1. Field of the Invention
This invention relates generally to tools used to complete subterranean wells and more particularly provides an apparatus for use in gravel pack operations.
2. Description of Related Art
Hydrocarbon fluids such as oil and natural gas are obtained from a subterranean geologic formation, i.e., a reservoir, by drilling a well that penetrates the hydrocarbon-bearing formation. Once a wellbore has been drilled, the well must be completed before hydrocarbons can be produced from the well. A completion involves the design, selection, and installation of equipment and materials in or around the wellbore for conveying, pumping, or controlling the production or injection of fluids. After the well has been completed, production of oil and gas can begin.
Sand or silt flowing into the wellbore from unconsolidated formations can lead to an accumulation of fill within the wellbore, reduced production rates and damage to subsurface production equipment. Due to its highly abrasive nature, sand contained within production streams can result in the erosion of tubing, flowlines, valves and processing equipment. The problems caused by sand production can significantly increase operational and maintenance expenses and can lead to a total loss of the well. One means of controlling sand production is the placement of relatively large sand (i.e., xe2x80x9cgravelxe2x80x9d) around the exterior of a slotted, perforated, or other type liner or screen. The gravel prevents the fine sand from packing off around the production tubing and screen, and the screen prevents the gravel from entering the production tubing. It is important to size the gravel for proper containment of the formation sand, and the screen must be designed in a manner to prevent the flow of the gravel through the screen.
In open hole completions that are gravel packed, a drilling fluid residue is left on the formation adjacent to the borehole in the form of a filter cake. Filter cake removal treatments are conventionally done through coiled tubing after gravel packing. This necessitates the pulling of the gravel pack assembly out of the well and running in the well with coiled tubing for filter cake removal or to spot post gravel pack fluids such as breakers, acids or corrosion inhibitors. The final production/injection tubing is then run in the well after the coiled tubing is removed. The ability to perform the steps of gravel packing, filter cake removal operations and post gravel pack fluid spotting on a single trip would save significant time and expense.
The present invention comprises an apparatus for use in gravel packing operations in wellbores. Some embodiments of the invention enable the running in, washing down, gravel packing, reversing excess slurry, and the spotting of post gravel pack fluids on a single trip.
One embodiment of the invention comprises a housing having an exterior and a longitudinal bore extending therethrough, and a lateral port providing a communication path between the housing longitudinal bore and the exterior of the housing. A first sleeve is disposed within the housing longitudinal bore that has a longitudinal passageway therethrough and is capable of being positioned in an upper position and a lower position relative to the housing. First and second lateral passageways extend through the wall of the first sleeve. A second sleeve is disposed within the first sleeve and also has a longitudinal passageway therethrough. The second sleeve is capable of being positioned in an upper position and a lower position relative to the first sleeve. A first flow passage extends longitudinally through the housing and a second flow passage extends longitudinally through the housing. When the first sleeve is in the upper position, and the second sleeve is in the lower position, communication is established between the longitudinal bore of the housing above the second sleeve and the exterior of the housing, and communication is established between the longitudinal bore of the housing below the second sleeve and the first flow passage. When the first sleeve is in the lower position, communication is established between the longitudinal bore of the housing above the first sleeve and the second flow passage.
The apparatus can have the first and second sleeves releasably secured in their upper positions with retaining elements. The retaining elements can be of a shear element design.
The first and second sleeves can comprise ball seating elements, where the ball seating element of the second sleeve has a smaller diameter than the ball seating element of the first sleeve. The apparatus can further comprise a first ball that can be sized so as to pass through the first sleeve, and to seat within the second sleeve. When the first sleeve is in the upper position and the first ball is seated within the second sleeve, the first ball can form a primary seal that restricts communication between the longitudinal bore of the housing above the second sleeve and the longitudinal bore of the housing below the second sleeve. The invention can further comprise a second ball that is sized so as to seat within the first sleeve. When the first sleeve is in the upper position and the second ball is seated within the first sleeve, the second ball forms a seal that restricts communication between the longitudinal bore of the housing above the second ball and the longitudinal bore below the second ball.
The first sleeve can be in sliding contact with the housing and the second sleeve can be in sliding contact with the first sleeve.
When both the first and second sleeves are in the upper position, the second sleeve prevents communication between the longitudinal bore of the housing and the first lateral passageway. When the second sleeve is in the lower position, a secondary seal can be formed by contact of the second sleeve with the first sleeve that restricts communication between the longitudinal bore of the housing above the second sleeve and the longitudinal bore of the housing below the second sleeve. This secondary seal can comprise an elastomeric sealing element, which can be an O-ring element, for example.
When the first lateral passageway is aligned with the lateral port, communication is established between the longitudinal bore of the housing above the second sleeve and the exterior of the housing, and communication is established between the longitudinal bore of the housing below the second sleeve and the first flow passage.
When the first sleeve is in the lower position, the second lateral passageway is aligned with the second flow passage and communication is established between the longitudinal bore of the housing above the first sleeve and the second flow passage. This can also establish communication between the longitudinal bore of the housing above the first sleeve and the longitudinal bore of the housing below the second sleeve through the second flow passage. When the first sleeve is in the lower position, the first sleeve restricts communication between the longitudinal bore of the housing and the lateral port and can also restrict communication between the longitudinal bore of the housing and the first flow passage.
The apparatus can be connected to a gravel pack screen element, to a packer element, and to a tubing string, each having a longitudinal bore. These tubulars can be located inside a wellbore, wherein an annular space is formed between the tubing and the wellbore. Communication can be established between the longitudinal bore of the tubing and the longitudinal bore of the gravel pack screen element.
An alternate embodiment of the present invention comprises a cylindrical housing having an exterior and a longitudinal bore and a lateral port communicating between the housing longitudinal bore and the exterior of the housing. A first sleeve is disposed within the housing longitudinal bore and in sliding contact with the housing, having a longitudinal passageway and a ball seating element. It is capable of being positioned in an upper position and a lower position relative to the housing and can have a first and second lateral passageways extending through the wall of the first sleeve. A second sleeve can be disposed within the longitudinal bore of the first sleeve, in sliding contact with the first sleeve and have a longitudinal passageway and a ball seating element. It can be capable of being positioned in an upper position and a lower position relative to the first sleeve. The embodiment can have a first flow passage extending longitudinally through the housing and a second flow passage extending longitudinally through the housing. A first ball is sized so as to pass through the first sleeve, and to seat within the second sleeve and a second ball is sized so as to seat within the first sleeve. The ball seating element of the second sleeve has a smaller diameter than the ball seating element of the first sleeve. When the first sleeve is in the upper position and the second sleeve is in the upper position, communication is established between the longitudinal bore of the housing above the sleeves and the longitudinal bore of the housing below the sleeves. The first lateral passageway is prevented by the second sleeve. When the first sleeve is in the upper position and the second sleeve is in the lower position, the first lateral passageway is aligned with the lateral port and communication is established between the longitudinal bore of the housing above the second sleeve and the exterior of the housing through the lateral port and communication is established between the longitudinal bore of the housing below the second sleeve and the first flow passage. When the first sleeve is in the lower position, the second lateral passageway is aligned with the second flow passage and communication is established between the longitudinal bore of the housing above the sleeves and the longitudinal bore of the housing below the sleeves through the second flow passage, communication between the longitudinal bore of the housing and the exterior of the housing through the lateral port is prevented by the first sleeve, and communication through the first flow passage is prevented by the first sleeve.
The apparatus can be located above and connected to a gravel pack screen element having a longitudinal bore and the apparatus can be located below and connected to a packer element having a longitudinal bore. The packer element can be connected to a tubing string having a longitudinal bore and the packer element inserted inside a wellbore, thereby forming an annular space between the tubing and the wellbore.
When the first sleeve is in the upper position and the second sleeve is in the lower position, the first lateral passageway is aligned with the lateral port and communication is established between the longitudinal bore of the housing above the second sleeve and the exterior of the housing through the lateral port and communication is established between the longitudinal bore of the housing below the second sleeve and the annular space above the packer element through the first flow passage.
When the first sleeve is in the lower position, the second lateral passageway is aligned with the second flow passage and communication is established between the longitudinal bore of the housing above the sleeves and the longitudinal bore of the housing below the sleeves through the second flow passage, communication between the longitudinal bore of the housing and the exterior of the housing through the lateral port is prevented by the first sleeve and communication between the longitudinal bore of the housing and the annular space above the packer through the first flow passage is prevented by the first sleeve.
The apparatus can further comprise a third lateral passageway through the first sleeve wherein when the first sleeve is in the upper position communication is established between the longitudinal bore of the housing below the sleeves and the first flow passage through the third lateral passageway. When the third lateral passageway is aligned with the first flow passage, communication is established between the longitudinal bore of the housing below the sleeves and the annular space above the packer element through the first flow passage.
A further embodiment of the invention includes an apparatus comprising a cylindrical housing having an exterior and a longitudinal bore and a lateral port communicating between the housing longitudinal bore and the exterior of the housing. A first sleeve can be disposed within the housing longitudinal bore, having a cylindrical wall and a longitudinal passageway therethrough, capable of being positioned in an upper position and a lower position relative to the housing. First and second lateral passageways can extend through the wall of the first sleeve. A second sleeve can be disposed within the first sleeve, having a longitudinal passageway and capable of being positioned in an upper position and a lower position relative to the first sleeve. A third sleeve can be disposed within the first sleeve, having a longitudinal passageway therethrough and capable of being positioned in an upper position and a lower position relative to the first sleeve. A first flow passage can extend longitudinally through the housing and a second flow passage can also extend longitudinally through the housing. When the first sleeve is in the upper position and the second sleeve is in the lower position, communication can be established between the longitudinal bore of the housing above the second sleeve and the exterior of the housing and communication can be established between the longitudinal bore of the housing below the second sleeve and the first flow passage. When the first sleeve is in the lower position and the third sleeve is in its lower position, communication is established between the longitudinal bore of the housing above the third sleeve and the second flow passage.
When the third sleeve is in its upper position, communication is restricted through the second lateral passageway. When the third sleeve is in its lower position, communication is possible through the second lateral passageway. The second and third sleeves can comprise ball seating elements. The ball seating element of the second sleeve can have a smaller diameter than the ball seating element of the third sleeve. The apparatus can further comprise a first ball that is sized so as to pass through the third sleeve and to seat within the second sleeve, and a second ball that is sized so as to seat within the third sleeve. When the first sleeve is in the upper position and the first ball is seated within the second sleeve, the first ball forms a primary seal that restricts communication between the longitudinal bore of the housing above the second sleeve and the longitudinal bore of the housing below the second sleeve.
The third sleeve can be in sliding contact with the first sleeve. The first and third sleeves can be releasably secured in their upper positions with at least one retaining element. When the first sleeve is in the upper position and the second sleeve is in the upper position, the second sleeve prevents communication between the longitudinal bore of the housing and the first lateral passageway.
Yet another embodiment of the invention comprises a circulation tool having a housing with a longitudinal bore, a wall, and at least one lateral port through the housing wall. It can include at least two sliding sleeves, at least one flow passage within the housing wall and a plurality of circulation paths that can be created by the selective positioning of the sliding sleeves.
The circulation tool can comprise a first sleeve movable between an upper position and a lower position and a second sleeve movable between an upper position and a lower position. The second sleeve is capable of being shifted into its lower position independent of the movement of the first sleeve.
When the first and second sleeve are in their upper position, fluid communication is established through the longitudinal bore of the tool and restricted through the lateral port through the housing wall, creating a standard circulation path.
When the second sleeve is in its lower position and the first sleeve is in its upper position, fluid communication is established between the longitudinal bore of the housing above the second sleeve and the lateral port through the housing wall. Fluid communication is also established between the longitudinal bore of the housing below the second sleeve and the first flow passage, creating a gravel pack circulation path.
When the second sleeve is in its lower position, the first sleeve in its lower position, and the third sleeve is in its lower position, fluid communication is restricted between the longitudinal bore of the housing above the first sleeve and the lateral port through the housing wall. Fluid communication is established between the longitudinal bore of the housing above the first sleeve and the second flow passage. Fluid communication is also established between the longitudinal bore of the housing below the second sleeve and one of the flow passages within the housing wall, creating a modified standard circulation path.
Another aspect of the present invention consists of a method of completing a subterranean well that comprises tubing and an annulus between the wellbore and the tubing. The method comprises providing a device as described above and positioning the device within a wellbore wherein the first sleeve is in the upper position and the second sleeve is in the upper position. The device is reconfigured so that the second sleeve is in the lower position, allowing communication between the longitudinal bore of the housing and the exterior of the housing. The device is reconfigured so that the first sleeve is in the lower position, allowing circulation through the tubing and device and up the tubing/wellbore annulus.
This method can further comprise using a first ball to reposition the second sleeve from the upper position to the lower position. A second ball can be used to reposition the first sleeve from the upper position to the lower position. The method can further comprise attaching a gravel pack screen assembly below the device and a packer element above the device prior to positioning the device within the wellbore. A gravel laden slurry can be flowed through the lateral port when the first sleeve is in the upper position and the second sleeve is in the lower position, thereby depositing the gravel in the annulus adjacent the gravel pack screen assembly. The device can be released from the gravel pack screen assembly after the gravel laden slurry is placed and the wellbore circulated through the tubing and the device after the first sleeve is in the lower position to place fluids at desired locations within the wellbore.
An alternate embodiment of the invention includes a wellbore completion method comprising providing a circulation tool as described above, positioning the tool within the wellbore, thereby creating a tool-wellbore annulus. The tool is initially configured to provide a first circulation path, the first circulation path being through the tool and the tool-wellbore annulus. The tool can then be reconfigured to provide circulation through the lateral port to provide a second circulation path. The tool can then be reconfigured to seal off the lateral port and provide a third circulation path through the tool and the tool-wellbore annulus. The tool can be reconfigured from the first circulation path to the second circulation path utilizing a first ball and from the second circulation path to the third circulation path utilizing a second ball, the balls sized to seat within the sliding sleeves. The method can further comprise attaching a gravel pack screen assembly to the tool. A gravel laden slurry can be flowed through the second circulation path, thereby depositing gravel within the wellbore outside of the gravel pack screen assembly. Fluids can then be circulated within the wellbore through the third circulation path, following the depositing of gravel outside of the gravel pack screen assembly.
An alternate embodiment of the invention is a well completion method performed in a single trip into a well. The method comprises inserting a service tool into the well to a desired location, gravel packing the well, and circulating fluids within the wellbore through the service tool to dislodge and remove filter cake residue. The gravel packing can comprise flowing a gravel laden slurry through the service tool, thereby selectively depositing gravel within the well. The service tool can define multiple, selectable flow paths through which fluids and slurries can flow. When the service tool is inserted into the well it can be in a first flow path configuration that allows circulation through the service tool. Once the service tool has been inserted to the desired location, the service tool can be reconfigured to a second flow path configuration to enable the gravel packing of the well. After the well has been gravel packed, the service tool can be reconfigured to a third flow path configuration to enable the circulation of fluids within the wellbore, through the service tool, to dislodge and remove filter cake residue. After the circulation of fluids to dislodge and remove filter cake residue, specialty fluids can be spotted at selected locations within the well.
Yet another embodiment is a method of completing a subterranean well performed in a single trip into a wellbore. This method comprises running a service tool into the well, the service tool defining multiple, selectable flow paths and the gravel packing of the well. A different flow path of the service tool is selected followed by the removing of a filter cake from the wellbore by circulating a fluid through the service tool. Specialty fluids are spotted within the wellbore at desired locations prior to the removing of the service string from the well. The gravel packing of the well can comprise flowing a gravel laden slurry through the service tool, thereby selectively depositing gravel within the wellbore. The service tool can be inserted into the well in a first flow path configuration allowing fluid circulation through the service tool. When the service tool has been inserted to the desired location, the service tool can be reconfigured to a second flow path configuration to enable the gravel packing of the well.
In still another embodiment a well completion method performed in a single trip into a well is disclosed. This method comprises inserting a service tool into the well to a desired location and gravel packing the well with a fluid that contains at least one breaker for filtercake removal. Fluids are then circulated or injected within the well through the service tool to displace the breakers away from predetermined downhole equipment. The service tool can be inserted into the well in a first flow path configuration allowing fluid circulation through the service tool. When the service tool has been inserted to the desired location, the service tool can be reconfigured to a second flow path configuration to enable the gravel packing of the well. Once the gravel packing of the well has been performed, the service tool is capable of being reconfigured to a third flow path configuration to enable the circulating of fluids through the service tool.